I've only seen a few episodes, mainly when I'm flipping through channels and I notice it's on, It seems really interesting, but when I see things like this it brings up a bunch of questions (by the way, the I can only remember two episodes specifically, both with what this post calls the tenth doctor, in one he was on a planet rotating a black hole and some guy was possessed by the devil and had a bunch of black letters on his body and a bunch of zombie like aliens doing all the work and the doctor goes into a deep pit and finds the devil chained there, the other episode he was in a place where there was an elevator and he uses his screwdriver to hack the elevator and makes it take him to the highest floor where a guy who knew the doctor had gone and had a connection installed on his forehead causing the alien on the top floor to learn the doctor's secrets)
Anyway, if anybody reads this and can answer these questions, please do because google is really no help

One: Why is there so many doctors? I've gathered that when the doctor dies another one shows up, but is it the same doctor just in a different body?

Two: on the devil episode I mentioned, the doctor seemed relieved when he found his phone booth which begged the question, does the phone booth take him somewhere then hide until needed or something, the heck is up with that?

Three: who are these companions, Is it just people who the doctor happened to run across and decided to take with him or are they special somehow? How the heck can a companion go with more than one doctor?

Fourth and most wanted: Who is the doctor? is he a time traveler looking for answers to something or does he look for things that happened that shouldn't have, he seems to know everything so is he just looking to expand his knowledge or is he just running around for fun. seriously I have no idea what he IS.

I wanna watch this show, but I have too many questions that I feel If I don't know the answers I won't understand the series

1. The doctor is a timelord, which means he can regenerate when he is about to die. That changes his body and characrter, but he's still the same person.
2. The phone booth is the TARDIS, which stands for Time And Relative Dimensions In Space. It can travel anywhere at any time.
3. The companions are specific people the doctor has taken a Liking to and then takes in his TARDIS.
4. The Doctor is a timelord from the planet Gallifrey. His planet and species was destroyed in a war, and he usually just runs around with his companions and has adventures.

When the show was revived in 2005, the writers did a really good job of answering those questions over the course of the season. I think if you were to start at Series 1 from 2005 and worked forward, all your questions would be answered with very little confusion.

The companions are basically audience surrogates, giving the Doctor a convenient excuse to explain everything out loud so that the audience can follow his thinking. This is especially true in the 2005 series, as the first companion is just as clueless as (if not more so than) a regular person.

People have kinda answered all your questions but I just want to bring up number four. The biggest question for all fans is "Doctor Who?" The surface stuff tells us that he is sort of a Time travelling vigilante who stole the Tardis, fled Gallafrey and subsequently became the last of his race. All in all, however, we don't know that much about him. He has a past which is shrouded in secrecy and probably for a good reason as well.

I haven't watched too many episodes, but I'll try to answer some of your questions.

1 + 4: The Doctor is the last of the Timelords. He is 900-ish years old at this point. When he "dies", he just regenerates into a different body -- a convenient thing for the show when the Doctor's actor becomes too old/quits/whatever.

2: The Police Box is the TARDIS (Time And Relative Dimensions In Space). Basically, it can go anywhere and anytime, and it's bigger on the inside! It's one of the Doctor's best tools and, without it, the show wouldn't be possible.

3: I think companions are just people who convince the Doctor to take them with him. They can be with more than one Doctor because, technically, all Doctors are the same Doctor, just in different appearances.